1. What do I feel inspired by?
2. What am I particularly talented at?
3. What meets a significant need in the world?
Think on these, and reassess (maybe monthly, or every other month) and I think it'll become clear to you what excites you, motivates you to action, and serves a higher purpose (which will inspire you further). Just keep moving - just as a rolling stone cannot change direction if it is not moving, God will begin to use you as you start taking steps. So don't worry about being perfect! Just start doing!